Construct an explanation based on evidence for how natural selection leads to adaptation of populations.

  1. Life

    How a moth went to the dark side

    Peppered moths and some butterflies are icons of evolution. Now scientists have found a gene responsible for making them so.

  2. Oceans

    Polar bears swim for days as sea ice retreats

    Melting sea ice is forcing polar bears to swim long distances — up to nine days in one case. Such long treks may be more than the bears can handle.

  3. Humans

    Slicing meat may have aided human evolution

    An experiment with modern-day humans shows how slicing meat could have saved human ancestors energy — and let their bodies and brains get bigger.

  4. Animals

    Mates or survival: Which explains a bird’s color?

    When male birds are brightly colored, we assume that’s because their plumage attracts the gals. But a new study with thousands of museum specimens shows that sometimes survival is just as important a factor behind bird color.

  5. Animals

    Ocean animals have mushroomed in size

    Compared to a half-billion year ago, sea creatures are, on average, roughly 150 times bigger, a new study finds.

  6. Fossils

    Dinos ‘quickly’ shrunk into birds

    Scientists had long known birds descended from dinosaurs. A study now shows that the morphing from dinos into birds went along with a quick and steady shrinking of their body sizes.

  7. Fossils

    This dino-bird is super-feathered

    This late-Jurassic dino was also a bird. Its ample coat of feathers emerged before any need for flight.

  8. Animals

    When a species can’t stand the heat

    When temperatures rise, New Zealand’s tuatara produce more males. With global warming, that could leave the ancient reptile species with too few females to avoid going extinct.

  9. Life

    Caught in the act

    Scientists observe some evolutionary speed demons as they adapt over the course of just a few years to new environmental conditions.

  10. Chemistry

    A plant enemy’s enemy

    Plants use chemicals to recruit help in fighting off pests.

  11. Fossils

    A really big (but extinct) rodent

    A rodent about the size of a bison once roamed the riverbanks of ancient Venezuela.